1. Field of the Invention
The present invention relates to a remote control system for a vehicle and more particularly a remote control system for a vehicle capable of controlling with use of a single portable transmitter a plurality of devices mounted on the vehicle.
2. Description of the Prior Art
Heretofore there has been known a remote control system for a vehicle of the type in which one transmission signal (say, a radio signal) is transmitted from a portable transmitter toward a receiver disposed in the vehicle (automobile) and is received by the receiver to control a device disposed in the vehicle, say, a remote-controlled locking device. By this remote-controlled locking device a control is made to lock a door and at the same time, if a window is open, a remote control for closing the window is also conducted.
In a vehicle equipped with such a control system a person (say, a driver) who holds the portable transmitter can control a plurality of devices disposed in the vehicle simultaneously. Even if the person who holds the portable transmitter forgets to close a window for example and leaves the vehicle, both locking the door and closing the window can be done at a time and that automatically by transmitting a remote lock control signal for locking the door from the portable transmitter to the receiver disposed in the vehicle. This is advantageous in point of theft prevention.
The above conventional remote control system (e.g., a door locking control system) can control the remote control system disposed in the vehicle (automobile) even from a fairly remote place (say, from a distance of about 20 to 30 meters) This means that the control can be made even from such a remote place as the portable transmitter holding person (say, the driver) cannot exactly confirm (visually) the condition of the vehicle (automobile) or even when there is an obstacle (say, another vehicle) between the portable transmitter holding person and the vehicle, making it impossible to see the vehicle directly.
In connection with the above example, if the portable transmitter holding person left the vehicle while leaving goods within the vehicle and transmitted a door lock command signal through the portable transmitter despite of it being impossible to exactly confirm (visually) the condition of the vehicle, and if at this time a window is open and the goods are fallen and project from the open window, not only a locking control is made but also the window is closed automatically and simultaneously. This closure of the window may give rise to the problem that the goods are caught in the window, resulting in the window being not closed or being broken.
The present invention solves the above-mentioned problem and it is an object of the invention to provide a remote control system for a vehicle wherein the contents of control are changed depending on the distance between the vehicle and a portable transmitter and wherein even with a lock command signal provided from the portable transmitter in a vehicle invisible condition for example, windows are not closed automatically.
The remote control system for a vehicle according to the present invention comprises:
a portable transmitter which transmits first and second transmission signals of different transmission distances together;
a receiver which is disposed in the vehicle and which receives the first and second transmission signals;
a control circuit section which outputs first and second control signals based on the received first and second transmission signals; and
first and second devices which are disposed in the vehicle and which are controlled and driven with the first or the second control signal,
wherein when the receiver has received at least the first transmission signal, the control circuit section outputs the first control signal and the first and second devices are driven, while when the receiver has received only the second transmission signal, the control circuit section outputs the second control signal and only the first device is driven.
Preferably, the first device is a vehicular door locking/unlocking mechanism and the second device is a window opening/closing mechanism.
Preferably, the transmission distance of the first transmission signal transmitted by the portable transmitter is shorter than that of the second transmission signal transmitted also by the portable transmitter.
Preferably, the first transmission signal transmitted by the portable transmitter is an infrared signal and the second transmission signal transmitted also by the portable transmitter is a radio signal.